There is evidence of an association between chronic alcohol intake and increased incidence of breast cancer, however, the cellular and molecular mechanisms of this relationship in human and in animals is not well understood. In the hamster kidney model, a bona fide estrogen target tissue, concomitant ethanol and estrogen treatment substantially increases in the incidence and number of kidney tumor foci compared to animals treated with hormone alone. The overall aim of this proposal is to elucidate the cellular and molecular events leading to enhanced estrogen-induced renal tumorigenesis in the hamster by ethanol (EOH). To pursue these goals the following studies are proposed: 1. Affect of Chronic Estrogen Treatment of EOH Metabolism in the Hamster Kidney. We propose to study whether prolonged estrogen treatment has a significant affect on EOH metabolism. Kidney and liver ADH and ALDH activities and microsomal liver and kidney changes in EOH inducible P-450 IIE1 will be studied. Also, the binding of [14C]-EOH product, acetaldehyde to liver and kidney microsomal proteins will be studied. 2. Reparative kidney cell proliferation in estrogenized hamsters, BrdU and PCNA (proliferation cell nuclear antigen) labeling studies. Systematic BrdU and PCNA labeling studies will be conducted in estrogen alone and 10% EOH + estrogen treated hamster kidneys. These studies should provide not only the temporal time period of enhanced labeled cells, but also the pattern (location), cell type, the frequency of individual cells in the cell cycle. 3. Role of Ethanol in Estrogen- Induced Aneuploidy and Chromosomal Abnormalities. Since EOH via ACH formation has shown in some mammalian systems to enhance aneuploidy and induce chromosomal aberrations and SCE, we will determine whether these genetic changes can be induced by EOH in the hamster kidney, whether the are similar (i.e. effect the same chromosomes) and whether the agents in combination lead to additional chromosomal alterations important to enhanced estrogen-induced neoplastic transformation in the Kidney. 4. In-site Localization of Protooncogene Expression in Hamster Kidney Cells Following Estrogen plus/minus Ethanol Treatment. We propose to determine the cellular expression of protooncogenes in estrogenized kidneys for different treatment periods employing in situ hybridization and immunolocalization techniques with hamster cDNA probes. Specific attention will be given to renal primitive interstitial "preneoplastic" foci which is significantly increased in EOH + DES treated hamster compared to DES alone.